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alexleyenda
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Be careful though, you should listen to this at 1:30 :p https://www.youtube.com/watch?v=u6MfZbCvPCw
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TheAlchemistPirate
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Hello I have some questions about the "synthesis?" of blasting gelatin, I am planning to blow up some stumps with dynamite sticks but I'm not 100%
sure about the procedure. First I was wondering what they mean by "low colloid nitrocellulose" I figure this is partially-nitrated nitrocellulose
meant for being more easily dissolved by solvents but I cant find anywhere showing the ratios for synthesizing it. Secondly I was wondering about the
sensitivity, I have seen some sources saying blasting gelatin is very shock-sensitive but others saying it requires high-level blasting caps??? But
yeah I hope you guys can help me out.
"Is this even science anymore?!"
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PHILOU Zrealone
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Quote: Originally posted by TheAlchemistPirate  | Has anyone here synthesized ruby? I have been looking around on the internet and am interested in making synthetic rubies, and have some questions. I
know that synthetic ruby is made by reacting chromium oxide with aluminum oxide at 2000+ degrees Celsius, but I have seen on this forum where someone
who did the reaction used a platinum-lined crucible to contain the reactants. I don't see why this would be necessary, since as far as I know the
reagents aren't acidic and don't need platinum as a catalyst. If a platinum crucible is required I will probably forget the idea since platinum is so
ridiculously expensive.
I also cant seem to find out how long the reactants need to be heated, I did see an article on the industrial process which apparently takes around 20
minutes...? The process involved using oxygen and hydrogen to heat the mixture and dripping the melted product onto a seed crystal, of course I cant
do this and was thinking of another method which involves dipping a rod with a seed crystal into a crucible filled with the mixture. The crystals
would then form on the rod.
I figured that I could use the latter method by making a furnace with firebrick and a graphite crucible, putting a graphite rod into the melted
mixture and getting the rubies. I would very much hope this would be the case as it would be very awesome to be able to make your own gemstones.
Unfortunately there isn't very much talk about homemade gemstone synthesis on the internet and all I can find is industrial processes, I hope you guys
can help. |
I did with Al2O3 powder, Cr2O3 powder into a refractive cement/clay reactor and with hobby acetylen/aceton/N2O welding blowtorch...as explained in a
topic initiated by you under general chemistry with "Subject: aluminium oxide crystal" : it is not very practical
CoO or FeO/TiO2 is used for saphire (blue corundum)
[Edited on 17-6-2014 by PHILOU Zrealone]
PH Z (PHILOU Zrealone)
"Physic is all what never works; Chemistry is all what stinks and explodes!"-"Life that deadly disease, sexually transmitted."(W.Allen)
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PHILOU Zrealone
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| Quote: Originally posted by alexleyenda | A very random question I wanted to ask for a long time: When I cook instant noodle, as soon as I dump them in the boiling water it starts to boil 3
times stronger, and if I push the block of noodles to the bottom, it boils even 3 times stronger again. Why the heck does it do that? I guess more
area for the bubbles to form like for boiling chips is part of the answer ?
 |
For the distillation pumice stones are used (those are kind of light lava stones with a lot of air bubbles (stone foam).
But one can also use sand.
The famous menthos into a sparkling soda proceeds by the same effect...but with addition of solubilisation of the menthos suggar and expelling the
dissolved gas.
PH Z (PHILOU Zrealone)
"Physic is all what never works; Chemistry is all what stinks and explodes!"-"Life that deadly disease, sexually transmitted."(W.Allen)
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PHILOU Zrealone
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| Quote: Originally posted by Pumukli | Hello All,
Could someone suggest an OTC-ish olefine, which is:
- preferably has the R-CH=CH2 or R-CH=CH-R' structure,
- preferably has its boiling point above 60 Celsius,
- and is not an aromatic one? (I mean one without an aromatic ring.)
By "OTC-ish" I mean: one can get it as an OTC product or can prepare it with a very simple one-step synthesis from an OTC product.
I can think of eugenole and styrene but these are aromatic. Cyclohexene on the other hand is not OTC-ish afaik.
Good brain-storming!
[Edited on 4-6-2014 by Pumukli] |
Lycopene from tomatoes.
Potassium sorbate.
Accrylic acid.
PH Z (PHILOU Zrealone)
"Physic is all what never works; Chemistry is all what stinks and explodes!"-"Life that deadly disease, sexually transmitted."(W.Allen)
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PHILOU Zrealone
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| Quote: Originally posted by alexleyenda | What would the greenish deposit on copper wire in a chlorate cell (not used as electrode in the liquid, only in the air) be? My guess is copper
chloride, am I right?
PS: I know it is not a good idea to put copper in there, I was juste making a small scale test before I get my MMO electrodes for the real thing
[Edited on 6-6-2014 by alexleyenda] |
If it is soluble an emerald green CuCl2; if it is unsoluble and like tuquoise green Cu(OH)Cl (copper oxychloride).
PH Z (PHILOU Zrealone)
"Physic is all what never works; Chemistry is all what stinks and explodes!"-"Life that deadly disease, sexually transmitted."(W.Allen)
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papaya
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Sorbitol
Where I live I can freely obtain sorbitol sugar substitute (crystalline) for experiments, however a quick google search reveals, that sorbitol
hydrates also exist besides anhydrous form
https://www.sciencedirect.com/science/article/pii/0040603188...
https://www.sciencedirect.com/science/article/pii/S000862159...
so how can I get sure if my stuff is anhydrous, or if even not - how to get the anhydrous form from it? I ask, because I'm nearly sure they wouldn't
put anhydrous form regardless what they're writing on the box, isn't it? Can it be dried by melting and keeping the melt at high T for a while?
[Edited on 17-6-2014 by papaya]
[Edited on 17-6-2014 by papaya]
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alexleyenda
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| Quote: Originally posted by PHILOU Zrealone | | Quote: Originally posted by alexleyenda | What would the greenish deposit on copper wire in a chlorate cell (not used as electrode in the liquid, only in the air) be? My guess is copper
chloride, am I right?
PS: I know it is not a good idea to put copper in there, I was juste making a small scale test before I get my MMO electrodes for the real thing
[Edited on 6-6-2014 by alexleyenda] |
If it is soluble an emerald green CuCl2; if it is unsoluble and like tuquoise green Cu(OH)Cl (copper oxychloride). |
It might be copper oxychloride, however it's been a while now, I don't have it anymore I can't test its solubility. Thank you for
the answer though.
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papaya
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So what about sorbitol?
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alexleyenda
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I tried to search about it and no one really seems to give any precise information about it :/
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papaya
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Well, I conducted an experiment, where I melted 5g of 'sorbitol' with unknown water content in a wide dish and let it stay at 130-150°C (at more than
250C it starts to fume - the polyol vaporizes too) for more than one hour. After cooling my 0.1g accuracy scales didn't detect any mass lose, so this
means there's no water OR it can't be dehydrated just by heating. Better scales are not available, the problem is that if there's undetectable
<0.1g loss, then it accounts as 2% water by weight, which is more than that in molar fractions. What do you think?
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alexleyenda
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Why is conc sulfuric acid slightly yellow most of the time? I have not found a credible source for an explanation. Some talk about sulfur, others
about organic material contamination ?
Is there a way to remove the yellow? I know that when it is black you can oxidise it with peroxide, but it doesnt work on the yellow.
Edit: it became colorless when it cooled down, I guess this has to do with SOx gas then??
[Edited on 21-6-2014 by alexleyenda]
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Metacelsus
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Hydrogen Chloride Fumes
I was dehydrating manganese(ii) chloride, when it started releasing HCl fumes. I think the manganese chloride (from alkaline battery MnO2)
might have had traces of iron(iii) in it, but the fumes seemed too much to be solely from that.
Does manganese (ii) chloride hydrate release HCl upon heating (Wikipedia says no, but something must have been causing those fumes!).
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alexleyenda
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Unknown purple spots
I made salicylic acid from basic hydrolysis (NaOH) of methyl salicylate ans it worked well, but after the neutralisation with sulfuric acid I noticed
the solution took a purple color and left a very strong purple color on the filter paper. Any Idea why and what it could be?
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DraconicAcid
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| Quote: Originally posted by alexleyenda | | I made salicylic acid from basic hydrolysis (NaOH) of methyl salicylate ans it worked well, but after the neutralisation with sulfuric acid I noticed
the solution took a purple color and left a very strong purple color on the filter paper. Any Idea why and what it could be? |
Ferric ion in the acid reacts with phenols (including salicylic acid) to give highly coloured complexes.
Please remember: "Filtrate" is not a verb.
Write up your lab reports the way your instructor wants them, not the way your ex-instructor wants them.
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elementcollector1
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| Quote: Originally posted by Cheddite Cheese | I was dehydrating manganese(ii) chloride, when it started releasing HCl fumes. I think the manganese chloride (from alkaline battery MnO2)
might have had traces of iron(iii) in it, but the fumes seemed too much to be solely from that.
Does manganese (ii) chloride hydrate release HCl upon heating (Wikipedia says no, but something must have been causing those fumes!).
|
Somewhat curiously, some MnO2 I prepared once also gave off HCl (it had been prepared from battery sludge via hydrochloric acid). Related
phenomenon?
Elements Collected:52/87
Latest Acquired: Cl
Next in Line: Nd
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alexleyenda
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| Quote: Originally posted by DraconicAcid | | Quote: Originally posted by alexleyenda | | I made salicylic acid from basic hydrolysis (NaOH) of methyl salicylate ans it worked well, but after the neutralisation with sulfuric acid I noticed
the solution took a purple color and left a very strong purple color on the filter paper. Any Idea why and what it could be? |
Ferric ion in the acid reacts with phenols (including salicylic acid) to give highly coloured complexes. |
So
my acid would have ferric ions contamination? Is that common (because you seem to have directly targeted the acid as the source)?
[Edited on 24-6-2014 by alexleyenda]
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DraconicAcid
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| Quote: Originally posted by alexleyenda | | So my acid would have ferric ions contamination? Is that common (because you seem to have directly targeted the acid as the source)?
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I don't know how common it is for sulphuric acid to be contaminated with iron, but hydrochloric commonly is. But purple with salicylic acid is
definitely iron(III).
Please remember: "Filtrate" is not a verb.
Write up your lab reports the way your instructor wants them, not the way your ex-instructor wants them.
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alexleyenda
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Alright thanks for your very useful answer, as always. I'll make a few tests tomorrow to investigate the contamination.
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alexleyenda
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A question again, I seem to be over-using this thread but I've just always got hard to answer or random questions all the time^^
So, for some reasons i've got bismuth metal over silver metal, is there any way I can separate them to recover only the silver? From my researches I
found that both almost only get dissolved in nitric acid and their nitrate salt's solubility is similar so... Is there any way I can dissolve the
bismuth to keep only the silver? (or dissolve the silver to get rid of the bismuth. My final goal is to get pure silver nitrate)
[Edited on 26-6-2014 by alexleyenda]
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bismuthate
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Theoretically copper chloride should dissolve it slowly. But if I were you I would dissolve it all in nitric acid then displace the silver with
copper.
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alexleyenda
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Right, bismuth's redox potential is right under copper...Then to get rid of the copper I could dissolve what's left in HCL+H2O2... Then dissolve the
silver again in HNO3?
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Brain&Force
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Bismuth chloride is soluble in acids, silver chloride is insoluble. You could also try leaving silver in solution by means od a diammine complex.
At the end of the day, simulating atoms doesn't beat working with the real things...
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alexleyenda
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Right, so my idea to get rid of the copper with HCl + H2O2 (to get a solution of CuCl leaving the silver intact) should work, I'll try it.
Another question, something I could not explain arrived... I was preparing my electrolyte solution to top up my chlorate cell. I used the "waste"
water from the recristallisation of my last batch to avoid wasting the ions and the dichromate left it in, so it contained very little K2Cr2O7 that
gave it a pale yellow color, and the KCl I added. I left it outside for an hour and a half on a hot day under the sun because I had something else to
do. When I came back, the solution had become colorless, it lost its slight chromium yellow color. Why ? I suspect electromagnetic rays have something
to do with it but... ?
After that, I started heating it to dissolve the KCl to the temperature of my cell, but it didn't dissolve completely. I added some of the solution
that was already in my cell (containing a 3g/L K2CR2O7 and what was left over of KCl and KClO3 from the last batch) to dissolve what was left of the
KCl... The solution in the cell was a moderate yellow, the solution in the hot erlenmeyer was colorless... at the second they mixed, it became a very
dark green ! Now for this one I would bet on Chromium(III) oxide, though I have no idea why it would have happened.
In brief: Why did it become colorless, am I right to think the green was caused by Chromium(III) oxide and if I am, how did Chromium(III) oxide form?
Additional Info: In the KCl used, there are these additives in small quantity: Potassium bitartrate, adipic acid silicon dioxide, mineral oil and
fumaric acid.
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bismuthate
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Could the colourless stage somehow be potassium chromite? I have no idea how it could have formed but it would explain the clear colour.
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